s1 = 'hello, world!'
s2 = "你好，世界！❤️"
s3 = '''hello,wonderful world!'''
print(s1)
print(s2)
print(s3)
s1 = '\141\142\143\x61\x62\x63'
s2 = '\u9e4f\u71d5\u662d'
print(s1)
print(s2)
for i in s1:
    print(i)
for i in range(len(s1)):
    print(s1[i])
s = 'hello, world!'
print(s.find('or'))
s1 = '   jackfrued@126.com  '
print(s1.strip())      # jackfrued@126.com
a = '张三'
b = a.encode('utf-8')
c = a.encode('gbk')
print(b) #  b'\xe5\xbc\xa0\xe4\xb8\x89'
print(c) # b'\xd5\xc5\xc8\xfd'
print(b.decode('utf-8')) # 张三
print(c.decode('gbk')) # 张三